Low blood antioxidant concentrations are associated with several major degenerative diseases including cardiovascular disease and Cancer. Animal, cellular and chemical experiments have elucidated biologic mechanisms consistent with antioxidant protection against several disease processes. Determinants of blood antioxidant conCentrations are not well understood in young adults. We propose to measure serum concentrations of alpha tocopherol, selenium and all major carotenoids (alpha- and beta- carotene, lutein, (beta-cryptoxanthin and lycopene) in black and white, male and female, high and low education individuals aged 18-30 in 1985- 86. The analysis will be done using serum stored at 70 degrees Celsius, collected in 1985-86 (n=5115) and 1992-93 (n=4086). These analytes are stable in serum samples collected, handled and stored under conditions used in this study. Integrity of the chemical analysis throughout the study will be maintained by proven laboratory quality control procedures. Monitoring analyte concentrations in serum from collections seven years apart will allow analysis of age and time dependent changes in serum antioxidants. These data will be linked with extensive pre-existing sociodemographic, dietary, other behavioral and physiologic data for the cohort. Statistical analyses will provide information on the population's serum antioxidant distribution, tracking, change and major determinants in diverse young adults. In addition, these data will establish baseline and 7-year change concentration values for followup of this large cohort, though the relationship of these serum antioxidants to disease endpoints is not itself part of the workscope of this application. Study of plasma ascorbic acid, which is not stable under our storage conditions, will be initiated using fresh samples to be collected in 1995-96 (n=4000). The main scientific outcome of this research will be information on distribution and correlates of blood antioxidant concentrations, useful for formulating public health messages concerning maintenance of adequate levels of alpha tocopherol, selenium, ascorbic acid and the carotenoids.